UV diodes for full time use

MidnightSun72 · Oct 15, 2021

Looking to add either 4 or 8 UVA diodes around 365nm to my lights.

I am not really sure what the appropriate amount of radiation is or what the best way to compare UV diodes is. Just figure it out from the mW radiation vs input watts??

I am running 756W@ boards of white Bridgelux LEDs. I want to integrate the UV diodes to eat up some of drover voltage over head and gain benefits of UV. Trying to figure out how much UV radiation I need so I can run the lights in veg or flower.

essentially I am looking for the signalling effects of UV like larger more durable leaf growth and to help open the stomata. I like my plants to stretch a little so I'll be adding 730nm as well to counteract the growth suppression.Any tips on 730nm wattage? I am looking for around 30-50W IR per light. Specifically the QB20 boards offered by kingbrite.

also tryna be economic cuz I gotta do 6-8 fixtures.

so far one of my favourite options is some LG UV diodes mounted to star PCBs draw 3.8V and 0.7a to make around 6-700mw.
Specs below.

and another note. Will this amount of Uv diodes be hazardous to my eye health? I gotta admit I don't always remember my glasses in the grow room. As in will it be more hazardous than normal sunlight? Would it be worth investigating some kind of circuit that will let me cut the UV out when I am in there?

Rocket Soul · Oct 15, 2021

Some notes:
- sun light contains about 3% uva but that's the total; 365nm seems to be the most reactive for the plant so I'm not suggesting 3 % of 365nm all day. If you want something for all day I'd go for something between 400-420nm: this will have similar effects on your plants but also contribute to photosynthesis.
- afaik uv does not make your leaves larger, rather the opposite. It's effect is very similar to the blue-response: smaller leaves, shorter internode spacing, increased transpiration slightly lower fruit/bud yield if not compensated for by red/far red. Think about what would be convenient for a tree in the top cannopy.
- Far red: does infact increase the leafsize due to shade avoidance syndrome. But how much do you need? Hard to tell.

My way forward in your case would be doing a smaller test on one light with uv and far red on separate dimmable channels. I'd get a little extra wattage of both uv and far red to get an idea of how they interact. If you find you have too much you can always run it soft or spread the chips out to later lights once you have established a baseline.

As for having it on same driver as the rest:
I'd try to run it at less than 500mA if your light is low hanging and really focus more on the spread instead of the wattage, making sure you got the uv nicely spread out. It's possible to burn your crop with uv even if your wattage is in good proportions if you run your diodes to hard.

MidnightSun72 · Oct 15, 2021

Rocket Soul said:
Some notes:
- sun light contains about 3% uva but that's the total; 365nm seems to be the most reactive for the plant so I'm not suggesting 3 % of 365nm all day. If you want something for all day I'd go for something between 400-420nm: this will have similar effects on your plants but also contribute to photosynthesis.
- afaik uv does not make your leaves larger, rather the opposite. It's effect is very similar to the blue-response: smaller leaves, shorter internode spacing, increased transpiration slightly lower fruit/bud yield if not compensated for by red/far red. Think about what would be convenient for a tree in the top cannopy.
- Far red: does infact increase the leafsize due to shade avoidance syndrome. But how much do you need? Hard to tell.

My way forward in your case would be doing a smaller test on one light with uv and far red on separate dimmable channels. I'd get a little extra wattage of both uv and far red to get an idea of how they interact. If you find you have too much you can always run it soft or spread the chips out to later lights once you have established a baseline.

As for having it on same driver as the rest:
I'd try to run it at less than 500mA if your light is low hanging and really focus more on the spread instead of the wattage, making sure you got the uv nicely spread out. It's possible to burn your crop with uv even if your wattage is in good proportions if you run your diodes to hard.

I typically have 2ft or more between plants and lights. But I would like to start growing right into them to save some wattage or yield a taller plant.

Moflow · Oct 16, 2021

@MidnightSun72 maybe this might help.
Will this amount of Uv diodes be hazardous to my eye health?
Yes.
I picked up a bargain in a uv led light a few weeks ago. It's called the Mantis.
£50 I really shoulda bought 2 and run them off one driver.
10 diodes, 5 x 365nm + 5 x 405nm. Seoul Viosys
Size 600mm x 100mm
~25 watts
I wish they were more spread out to be honest but I'll take it for the price.
Recommendations
For use in 1 m²
Run The MANTIS for a maximum of 4 hours each day for the last 4 weeks of the bloom phase for optimal performance. Preferably in the middle of the 12 hour light cycle.
You must keep your main luminaire(s) on while adding the UV bath.
Make sure not to look directly at The MANTIS while it is running, UV radiation can be dangerous to your eyes and skin.

I just followed the manufacturer instructions and I'm running it for four hours mid cycle of main lights 12 on 12 off.
The lights are about a foot away.
I do all work in the grow room at start of main lights on so the UV is Never on when I'm in there

UV diodes for full time use

MidnightSun72

Well-Known Member

Rocket Soul

Well-Known Member

MidnightSun72

Well-Known Member

Moflow

Well-Known Member

Similar threads